Chock block



Mai 15, 1934- N. T. MacKENzlE. 1,959,299

CHOCK BLOCK Filed April 1l, 1932 Patented May 15, 1934 UNITED STATES CHoCK BLOCK Neal T. MacKenzie, St. Paul, Minn., assignor to General Timber Service, Ine., St. Paul, Minn., a corporation of Delaware Application April 11, 1932, Serial No. 604,531

4 Claims.

This invention relates to chock blocks particularly, although not exclusively, adapted for use in securing motor vehicles against movement rin railway cars.

Large numbers of wooden blocks are used for this purpose in the automobile industry, but the more eflicient of such blocks have heretofore embodied so much lumber that the price is adversely affected. Because of the large number of blocks employed a comparatively slight difference in cost per block results in a large saving in the aggregate.

It is the object of this invention to provide a highly eliicient and secure block of this kind at. a

substantially reduced cost.

A specific object is to provide efficient chock blocks adapted to be constructed from lumber scrap not exceeding 4" x 4" in cross sectional size and containing not to exceed about one board foot of lumber in each block.

The invention will be best understood by reference to the accompanying drawing in which Figure 1 is a side elevation showing a pair of my chock blocks as they are used in securing a vehicle against movement;

Fig. 2 is a perspective view of one of the blocks;

Fig. 3 is a plan view of the same, looking at the seat for the vehicle tire;

Fig. 4 is a rear elevation showing one of the face pieces in detail; and

Fig. 5 is a diagrammatic view showing an economica-l method of cutting a piece of standard framing lumber to form a multiplicity of the main body blocks for the device.

The device has a main body block 6 preferably consisting of a short section of a common 4 x 4" piece of framing lumber. The block 6 has a plane base surface 7 extending at an angle of about 50 to the direction of the grain. A normally upper end surface 8 of the block 6 is formed by a plane out extending across the grain. Se-

cured to the surface 8 is a face piece 9 in which the grain extends horizontally, as indicated in Fig. 2, with the ends of the piece projecting from the sides of the block 6. A wide seat 10 for a vehicle tire 1l is formed in the upper face of the piece 9 by cutting away the central portion leaving rounded projections 12 to engage the sides of the tire.

A mortise or groove 13 (Fig. 4) is arranged to receive the upper end of the block 6 so that said end of the block is conned against splitting laterally and the seat 10 has a narrow transverse groove 14 to receive a large staple 15 for securing 1 5 5 the face piece 9 to the block 6. The staple 15 re- (Cl. 18S-32) inforces the piece 9 against lateral splitting and the tire 11 is protected against chaiing by the counter-sinking of the staple in the groove 14. A heel 16 of the block 6 projects and has holes 18 drilled therein to facilitate the driving of nails 19 for securing the block to the floor.

As best shown in Fig. 1, the radial planes of thrust exerted by the wheel in engagement with a pair of the chock blocks are indicated by the dotted lines a and these planes of thrust pass centrally through the face pieces 9 and intersect the base surfaces '7 approximately at the point of intersection of the nails 19 with said surfaces. By this arrangement, when the devices are in use, the components of the forces of inertia tending to withdraw the nails are reduced to a minimum. Unusual stability of the fastening is further secured in the present device by engaging the tire 11 at a point high above the iioor so that the dimension b (Fig. 1) is large. Where the planes a intersect the oor beyond or outside of the base surface of the chock block the stability of the fastening is adversely affected.

In Fig. 5 suitable angles for cutting a piece of framing lumber to form the blocks 6 is indicated SQ whereby a minimum of Waste and a stable form of block is secured. Thus the angle of the surface 'l to the front and back sides of the block is preferably about while the upper surface 8 extends at an angle of about 81 to the said sides. These angles are varied somewhat for vehicle wheels of different diameters. For maximum economy, the main body blocks of the device are cut from rough pieces of 4" x 4 framing scrap and the face pieces 9 are out from 2 x 4 stock -90 and are allowed to project from the sides of the block 6 sufficiently to afford a wide seat for the tire 11 which is commonly of considerably greater width than the block 6.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A chock block having in combination a Wood body having a base surface, the grain of the wood extending obliquely upward from said surface and a face piece secured to the upper end of said body '100 and projecting at opposite sides thereof, said face piece having the grain extending transverse the grain of said body and being formed with a seat for a tire in its upper surface and a mortise groove in its lower surface to receive a portion of said body.

2. In a chock block for engaging a vehicle wheel, a wood body having the grain of the wood extending substantially radially relative to said wheel and a face piece extending transverse the Vv110 upper end of said body and projecting at opposite sides thereof, said face piece affording a seat for a tire of greater width than said body and having a mortise connection with said body and means for connecting said face piece to said body.

3. A chock block having in combination a main body constructed from wood and formed with .a base surface extending obliquely relative to the grain of the wood, a face piece secured to the upper end of said body and formed with a depression to receive a vehicle tire, a heel projectingr from said body, means for securing said heel to. a support for the vehicle, the radial plane of 'thrust of said wheel extending from 1.the 'center of said face piece, downward approximately-tothe 1point of intersection between said securing means and the top surface of said support.

4. A chock block comprising a plurality of pieces of wood, one of said pieces constituting a body portion and another piece a face portion, said body portion having a base surface extending obliquely across the grain of the '.Wood and said face :piece y.extending transverse the upper end of said body piece and being formed with a seat for a tire and having the grain of the Wood extending substantially parallel to the axis of rotation of .the tire, said body piece being of less width than said seat for the tire and the ends of said face ,piece projecting at .the sides of said body piece.

NEAL T. MACKENZIE. 

